Gunderson
Double Stack Construction - Part 3
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view
With the basic structure of the car completed it was time to move to the smaller details. To save time making the drawings and to make sure all the parts fit; on several occasions I just drew the assembly of several parts in one drawing.
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As you
can see in this picture, I also layered the dimensions so that I
could pick out each part size. This may not be standard practice
in industry but it works for me. I knew what the width of the parts
would be so I basically extruded it when I laid out the sheet metal.
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This photo shows the parts made from the drawings. Also added and not shown on the drawing were the moveable locking block and the roll pin. The next operation was to bend the faceplate, the part with the square hole, and then to weld the parts together. |
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Here we see the bottom plate held in a “C” clamp using an aluminum spacer and heat sink to hold the parts in position for welding. I pre-machined the aluminum spacers to fit each job if it was a case where nothing else would work. I keep a box of random size aluminum blocks on hand for clamping and welding purposes. For those who are not into metals, the parts in this picture are made from .070 thick or 15 gauge steel. I use a Hobart wire feed welder with .030 wire to weld with. The steel wire in the welder will burn but not stick to the aluminum blocks. Therefore one does not have to worry about getting too close to the spacer. |
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Even with the block between the parts they will lean just a little toward each other as each is welded on the inside. |
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This picture of the brake end of the car shows some of the brake detail. Although as the Double Stacks roll by at 60 m.p.h. they don’t look like much with the smooth sides and low profile. However, there are probably more details on this car than anything I have built except a locomotive. |
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The next
view showing the “B” end of the car reveals the brake
pipe and pulleys for the hand brake. I haven’t gotten to the
walkways yet. The little parts sticking up are the brackets for
the future walkway.
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The photo of what I call the end bumpers or guides show the number of parts necessary for this particular detail. You won’t see the welds in this view as I find ways to hide most of them. This brings up a problem that one doesn’t encounter in most cars. Almost all the parts of this car are visible inside and out, end to end. It is a major challenge to obscure the connections of the materials. But, it is also part of the fun. |
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The next
photo shows the side bumpers (seen as parts at the top of this page),
attached to the car. This car has two different types of side bumpers.
One is raised up to allow the hand brake rod to move underneath.
These are the types of details that one has to search out by studying
all the information gained for a specific project. I would like
for a engineer from Gunderson to come up and say, “Yep, you
pretty well nailed it part for part…”
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The last couple of photos show the side view and view down the middle of the car. There is much more work to be done before it is complete. I would like to have it completed in the next 3 or 4 weeks. This has been a 6-month project so far, but a good learning experience. |  |
I have gotten quite dangerous with AutoCad, at least with orthographic drawings. My only disappointment has been that the parts require an extensive use of heavier metal and use of the milling machine on almost everything.
Here are a few new pictures of the brake assembly - from AutoCad models to final parts.
"Don’t try this at home" is a good saying for this project unless you have a band saw and a milling machine. I am keeping lots of drawings for the future however for those of you who may be so foolish to try. About 40 drawings so far and about 20 more to go.